Commercial Refrigeration Systems Flashcards
7 cards from real CFC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Commercial Refrigeration Systems flashcards as text
Under EPA Section 608, which of the following is NOT considered a violation when servicing commercial refrigeration equipment?
Answer: Recovering refrigerant before opening the system
Recovering refrigerant before opening the system is the required and compliant practice under EPA Section 608.
A commercial condensing unit is located on a rooftop and experiences high ambient temperatures in summer. Which control would help protect the compressor from overheating?
Answer: High-pressure cutout switch
A high-pressure cutout switch shuts down the compressor when discharge pressure exceeds a safe limit caused by high ambient temperatures and poor heat rejection.
In a commercial refrigeration system, subcooling of liquid refrigerant before the metering device primarily:
Answer: Increases refrigerating effect and prevents flash gas
Subcooling cools the liquid below its saturation temperature, increasing refrigerating effect and preventing flash gas formation at the metering device inlet.
A commercial supermarket case is experiencing short cycling of the compressor. Which condition is most likely causing this?
Answer: Low-pressure cutout set too high or system low on charge
A low-pressure cutout set too high or insufficient refrigerant charge causes suction pressure to rapidly drop below the cutout setpoint, causing frequent short cycling.
Which refrigerant was the first to be phased out under the Montreal Protocol due to its high ozone depletion potential (ODP)?
Answer: R-11 (CFC-11)
R-11 (CFC-11) has an ODP of 1.0 and was among the first refrigerants targeted for elimination under the Montreal Protocol's initial phase-out schedule.
In a commercial refrigeration system, oil return to the compressor is most critical when the system uses:
Answer: Flooded evaporators
Flooded evaporators maintain a pool of liquid refrigerant that can trap oil, making oil return design critical to prevent compressor oil starvation.
What does a high suction pressure combined with low discharge pressure typically indicate in a commercial compressor?
Answer: Worn or leaking compressor valves
Worn or leaking compressor valves reduce compression efficiency, allowing high-pressure gas to bleed back to the suction side, raising suction and lowering discharge pressure.